External JLink is required to program the board, so the console via RTT
is available anyway. It is much more convenient to use than soldering the
P4 connector and working with an external UART converter.
This implements the changes required to genreate the pdf version
of the documentation. The pdf will be generated as a build artifact
attached to the build. This is the first patch to enable this
a follow on patch to the website repo will publish the pdf to the
NuttX website.
